MonoTouch:带有InputView DatePicker的UITextField,由Landscape中的键盘隐藏

时间:2012-10-27 15:07:50

标签: uiscrollview xamarin.ios landscape uikeyboard

我有一个UITextField,我放在屏幕的底部:

UITextField Bottom of the screen

通常这个文本字段会被键盘隐藏,但我遵循了以下组合:

并创建了我的UITextField,当被选中时将显示日期选择器并且UITextField被自动滚动:

UITextField with DatePicker

这很有效,直到我将手机旋转到横向。

一旦进入横向,我的UITextField就会被推到太远的屏幕上,而不再被人看到。

Landscape UITextField DatePicker

在代码中我订阅UIKeyboard.WillShowNotification并调用下面的KeyboardWillShowNotification:

protected virtual void KeyboardWillShowNotification (NSNotification notification)
        {
            UIView activeView = KeyboardGetActiveView();
            if (activeView == null)
                return;

            UIScrollView scrollView = activeView.FindSuperviewOfType(this.View, typeof(UIScrollView)) as UIScrollView;
            if (scrollView == null)
                return;

            RectangleF keyboardBounds = UIKeyboard.FrameBeginFromNotification(notification);

            UIEdgeInsets contentInsets = new UIEdgeInsets(0.0f, 0.0f, keyboardBounds.Size.Height, 0.0f);
            scrollView.ContentInset = contentInsets;
            scrollView.ScrollIndicatorInsets = contentInsets;

            // If activeField is hidden by keyboard, scroll it so it's visible
            RectangleF viewRectAboveKeyboard = new RectangleF(this.View.Frame.Location, new SizeF(this.View.Frame.Width, this.View.Frame.Size.Height - keyboardBounds.Size.Height));

            RectangleF activeFieldAbsoluteFrame = activeView.Superview.ConvertRectToView(activeView.Frame, this.View);
            // activeFieldAbsoluteFrame is relative to this.View so does not include any scrollView.ContentOffset

            // Check if the activeField will be partially or entirely covered by the keyboard
            if (!viewRectAboveKeyboard.Contains(activeFieldAbsoluteFrame))
            {
                // Scroll to the activeField Y position + activeField.Height + current scrollView.ContentOffset.Y - the keyboard Height
                PointF scrollPoint = new PointF(0.0f, activeFieldAbsoluteFrame.Location.Y + activeFieldAbsoluteFrame.Height + scrollView.ContentOffset.Y - viewRectAboveKeyboard.Height);
                scrollView.SetContentOffset(scrollPoint, true);
            }
        }

两个补充功能:

protected virtual UIView KeyboardGetActiveView()
        {
            return this.View.FindFirstResponder();
        }

public static UIView FindFirstResponder (this UIView view)
    {
        if (view.IsFirstResponder)
        {
            return view;
        }
        foreach (UIView subView in view.Subviews) {
            var firstResponder = subView.FindFirstResponder();
            if (firstResponder != null)
                return firstResponder;
        }
        return null;
    }

    public static UIView FindSuperviewOfType(this UIView view, UIView stopAt, Type type)
    {
        if (view.Superview != null)
        {
            if (type.IsAssignableFrom(view.Superview.GetType()))
            {
                return view.Superview;
            }

            if (view.Superview != stopAt)
                return view.Superview.FindSuperviewOfType(stopAt, type);
        }

        return null;
    }

BitBucket上有完整的资源:https://bitbucket.org/benhysell/uitextfielddatepicker

关于我可能做错了什么的想法?

1 个答案:

答案 0 :(得分:1)

显示键盘时,您应该修改视图的高度。

这样的事情:

var frame = View.Frame;
frame.Height -= keyboardHeight;
View.Frame = frame;

获取键盘高度:

bool isLandscape = InterfaceOrientation == UIInterfaceOrientation.LandscapeLeft || InterfaceOrientation == UIInterfaceOrientation.LandscapeRight;
var keyboardFrame = UIKeyboard.FrameEndFromNotification (notification);
var keyboardHeight = isLandscape ? keyboardFrame.Width : keyboardFrame.Height;

只要您UITextField的{​​{1}}设置为中心,那么您的用户界面就应该正确。